Acer rubrum named ‘JSC Kingstwo’

ABSTRACT

A new and distinct  Acer rubrum  cultivar, named the ‘JSC Kingstwo’ maple is characterized by its variegated pigmentation of its leaves that varies with the age of the leaf; whereas, trees of  Acer rubrum  have no variegation known to the inventors. The ‘JSC Kingstwo’ maple is also characterized by its drought and cold tolerance.

Latin name: Acer rubrum.

Varietal denomination: ‘JSC Kingstwo’.

FIELD OF THE INVENTION

The present invention comprises a new and distinct cultivar of Acerrubrum and is referred to by the cultivar name ‘JSC Kingstwo’.

BACKGROUND OF THE INVENTION

This new cultivar of Acer rubrum, the ‘JSC Kingstwo’ maple, wasoriginally discovered as a naturally occurring limb mutation by JamesDavid Cavett in 2006 on one specific tree limb of an unnamed Acer rubrumtree planted in the yard of James D. Cavett at 74 S&W Lane, EstillSprings, Tenn. 37330. James D. Cavett took six cuttings off that singlebranch on the tree and rooted it in sand using Hormondin #3 (activeingredient is indole-3-butyric acid) at 74 S&W Lane, Estill Springs,Tenn. 37330 in July 2006. One of the 6 rooted cuttings survived. Sixtyrooted cuttings were started from the 1 surviving rooted cutting in July2007; these rooted cuttings were grown at 74 S&W Lane, Estill Springs,Tenn. Approximately 20 of the rooted cuttings begun in July 2007survived and were used to begin 150 new rooted cuttings in July 2008 and55 survived. In July 2009, approximately 250 rooted cuttings were takenand rooted in sand; approximately 125 rooted and survived. In July 2010,approximately 800 rooted cuttings were taken and rooted in sand;approximately 650 rooted and survived. In July 2011, approximately 2900rooted cuttings were taken and rooted in sand; approximately 2000 rootedand survived. Over the last 5 years all the rooted cuttings of ‘JSCKingstwo’ have exhibited the same growing characteristics and patternsas the parent tree, an unnamed Acer rubrum, except for the pigmentationof the leaves. The leaves of the rooted seedlings' pigmentation arereddish brown (172A-RHS) when the leaf breaks out of the bud. Withindays of emerging from the bud, the reddish-brown color is surrounded bya light green (145A-RHS) pigmentation. As the leaf enlarges, portions ofit become yellow (12A-RHS) until the large areas of the leaf becomelight yellow (8C-RHS) to whitish-yellow or cream (4D-RHS) color to white(N199D-RHS) mixed with green color (145A-RHS). Older growth leaves havespeckles of cream (4D-RHS) on a dark-green background (137A-RHS). JamesD. Cavett has been evaluating these propagated seedlings for 5 years.

James D. Cavett is solely responsible for finding this new cultivar onhis property, located at 74 S&W Lane, Estill Springs, Tenn. 37330. Allpropagation of this cultivar has been done by James D. Cavett at hisnursery, located at 74 S&W Lane, Estill Springs, Tenn. 37330.

James D. Cavett immediately recognized that the new cultivar, ‘JSCKingstwo’, exhibited new and distinctive leaf pigmentation. The leavesare reddish-brown when they first erupt from the bud. However, withindays of emerging the leaf exhibits a mosaic of reddish-brown surroundedby a light green pigmentation. As the leaf enlarges and matures, theleaf pigmentation becomes whitish-yellow (cream) and a light green. Themature leaf exhibits cream color surrounded by dark green regions. Allother growth characteristics of the cultivar are similar to the parenttree, an unnamed Acer rubrum. Only the seedlings that have originatedfrom rooted cuttings of the original rooted stem that James D. Cavettrooted in 2006, exhibit the leaf pigmentation that is attributed to thenew cultivar, ‘JSC Kingstwo’. Over the last five years, only the rootedcuttings have exhibited this pigmentation as compared to other Acerrubrum trees known to the Inventor.

As shown in the first two photographs (a 2-year old seedling taken Jun.22, 2008, labeled FIGS. 1 & 2) of the ‘JSC Kingstwo’ cultivar, thepigmentation of the leaves is distinctive and unique. The leaves thatare coming out of the apical bud are reddish-brown in color. The youngleaves immediately below the apical leaves retain this reddish-browncolor for up to a week but the reddish-brown is quickly surrounded by alight green color as chlorophyll is produced. Leaves further down thestem, have a variegated yellow-green, green-yellow, and light greencolor. More mature leaves are also variegated (FIG. 3) and exhibit mutedyellowish-green regions in a background of dark green and creampigmentation. Because the cultivar and the parent tree that it came fromare deciduous, the leaves turn color (from pink [56A RHS] to apurple-pink [68A RHS]). Other regions of the leaf exhibit a light yellow(15D RHS) color. The leaves drop off each fall in Zone 6b, whichincludes Middle Tennessee.

As shown in the third photograph (a 3-year old tree taken June 2009,labeled FIG. 3) of the ‘JSC Kingstwo’ cultivar, the pigmentation of theleaves is distinctive and unique. As the tree matures, not all leaveswill exhibit the same degree of variegation. Some leaves show morevariegation than others. For example, some will have more cream colorthan others. However, mature late summer leaves exhibit a variegatedcream and light green mixture of pigmentation surrounded by a dark greenpigmentation. The leaf has red petioles.

As seen in more detail (see FIG. 4), the seedling has an oppositearrangement. The leaves are 5 cm to 8 cm (or 2.0 to 3.1 inches) inlength and 7.6 cm to 16.5 cm (or 3.0 to 6.5 inches) in width. The leavesconsist of 3 to 5 shallow lobes with shallow tooth margins. The petiolesare red (47A-RHS) when the leaf first opens and remain red. The redpetioles persist into the fall as the leaves change color (see FIGS. 5 &6). The diameter of petioles are ˜0.3 to 0.4 cm and vary in length from2 cm to 3.5 cm.

FIGS. 5 and 6 show the characteristic colors that the fall leaves takeon. In early fall, the green chlorophyll begins to break down and isreplaced by a light pink (56A-RHS) hue in the cream-colored portions ofthe leaf that spreads into the once green-pigmented regions giving it apurple-pink (68A-RHS) color (FIG. 5). By late fall, the leaf colorbecomes predominately red-brown (179B-RHS) with small areas of the leafstill exhibiting the light cream color that was first seen in the earlyspring several days after the leaf emerged for its bud. The petioleremains red (47A-RHS).

There are several flower buds at the end of each stem (see FIG. 7) thatemerge in early spring (usually the end of February to early March inmiddle Tennessee) revealing sterile flowers that consist of 4 to 10stamen that are yellow-green (145B-RHS) on yellow (23A-RHS) stalks. Theflowers are encased in burgundy-red (45A-RHS) sepals before the floweremerges.

The ‘JSC Kingstwo’ cultivar has proven to be both drought resistant andwinter hardy. From mid-May until mid-June 2011, Middle Tennessee(climate Zone 6b, USDA Plant Hardiness Zone Map) experienced an unusualspring drought and for the first two weeks of June 2011, MiddleTennessee experienced the hottest first two weeks recorded in Tennesseein June in decades. This was a particularly dangerous and damagingdrought coupled with extreme heat because most of the trees had alreadybudded. The ‘JSC Kingstwo’ cultivar survived this drought and extremelyhot weather and continued to produce foliage throughout the spring andsummer months. All rooted cuttings taken from the trees exhibit the samemoderate growth that has been observed for the previous seasons that the‘JSC Kingstwo’ cultivar has been cultivated.

The ‘JSC Kingstwo’ cultivar can also endure drastic changes in moisture.‘JSC Kingstwo’ cultivar has been successfully grown without irrigationafter it was moved into the fields during its third season. Each summersince it was rooted in 2006, it has endured the drought that MiddleTennessee has experienced during the months of July and August. However,this spring (2011) we had an unusual drought in Middle Tennessee betweenmid-May to mid-June. The cultivar survived this early spring droughtwithout any irrigation.

The ‘JSC Kingstwo’ cultivar has been successfully propagated asexually.The proven means of asexual propagation has been rooted softwoodcuttings. During the first year, the stem that was discovered by JamesD. Cavett was rooted as six cuttings in sand at his nursery at 74 S&WLane, Estill Springs, Tenn. 37330; hence, only 6 cuttings were stuck insand in 2006. In July 2007, 1 rooted cutting survived and was used tostart 60 rooted cuttings in sand in July 2007 by James D. Cavett at hisnursery. In July 2008, approximately 20 of 60 rooted cuttings thatsurvived were used to begin 150 new rooted cuttings and 55 survived. InJuly 2009, 250 rooted cuttings were taken and rooted in sand;approximately 125 survived. In July 2010, 800 rooted cuttings were begunand approximately 650 survived. Approximately 2900 rooted cuttings werestuck in sand in July 2011 and 2000 survived. The cultivars haveretained all the characteristics of the original selected seedling. Ithas been successfully propagated through 5 generations of asexualreproduction with a survival rate between 33% the second year (2007),37% the third year (2008), 50% the fourth year (2009), and a 81%survival rate in the fifth year (2010). 69% of the cuttings havesurvived in 2011. Each generation has been stable and producedtrue-to-type trees each and every time the tree has been propagated.

The unique color of the leaves and moderate growth (3 to 6 feet peryear) of ‘JSC Kingstwo’ cultivar make it well suited for a variety oflandscaping uses. Furthermore, the ‘JSC Kingstwo’ cultivar is cold anddrought tolerant. The cultivar is a moderate size tree whose leafpigmentation is reddish-brown (172A-RHS) followed by a variegated lightyellow (8C-RHS) to cream (4D-RHS) and white (N199D-RHS) surrounded by alight green (145A-RHS) color in the weeks following their emergence fromthe bud. The mature leaf exhibits a variegated cream (4D-RHS) with asplash of light yellow (8C-RHS) and dark-green (137A-RHS) color. In thefall, the leaves turn from a variegated cream on a green background to apurple-pink (68A-RHS) mixture consisting of reds and pinks with a lightyellow (12A-RHS) in the creamy variegated portion of the leaf (see FIG.5) until the green pigmentation is replaced by the pink and purple-pink(68A-RHS) color interspersed with the variegated light cream color (seeFIG. 6). The unique color of the leaves of the ‘JSC Kingstwo’ cultivarwill make it a popular maple tree for those who desire attractivecoloration from early spring through the fall.

SUMMARY OF THE INVENTION

The following characteristics in combination distinguish the new treenamed ‘JSC Kingstwo’ cultivar from other cultivars of Acer rubrum knownto the Inventor.

1. The ‘JSC Kingstwo’ cultivar has a distinctive and unique variegatedleaf that the parent tree, an unnamed Acer rubrum, and other cultivarsof Acer rubrum known to the Inventor do not have. The colors of theleaves change throughout the growing season. The entire leaf is areddish-brown when it first emerges from its bud. Within a couple ofdays the leaf color is a mixture of this same reddish-brown color with alight green color. However, within two weeks, the reddish-brownpigmentation disappears and large areas of the leaf become variegated,culminating with a variegated light yellow color mixed with cream anddark green or white and dark green pattern in the mature leaf in latesummer/early fall. The cream and white regions found in the mature leafin the summer are initially replaced with different hues of pink colorand green regions of the summer leaf are replaced by a resplendentpurple-pink in the fall.

2. With the distinctive, variegated foliage colors that changethroughout the growing season, the ‘JSC Kingstwo’ cultivar will be apopular tree for landscaping applications. While it doesn't grow asquickly as other Acer rubum cultivars, it has a larger crown and morelimbs, and the leaves are not as deeply lobed.

3. The ‘JSC Kingstwo’ cultivar is cold tolerant, easily surviving thetemperatures experienced in Middle Tennessee (climate Zone 6b, USDAPlant Hardiness Zone Map).

4. The ‘JSC Kingstwo’ cultivar is able to endure drastic changes inmoisture levels. There is usually heavy rainfall in the spring and verylittle rain in July, August, and September in Middle Tennessee (climateZone 6b, USDA Plant Hardiness Zone Map). During the past 5 years thiscultivar has survived some severe drought conditions. In 2007, there waslittle rain in the spring and late summer. In 2011, there was an unusualtwo-week long, early spring drought that coincided with the hottesttemperatures for several weeks on record in Middle Tennessee for manydecades. Yet, the cultivar thrived. In summary, the ‘JSC Kingstwo’cultivar has survived annual summer droughts, including the severedrought during the summer of 2007 and endured record high temperaturesduring these drought conditions.

5. The ‘JSC Kingstwo’ cultivar grows at a moderate rate. The seedlingsgrew 3 to 4 feet during their first year and 5 to 6 feet during theirsecond year. During their third year, their average trunk size measured4.38 cm or 1.7 inches.

6. After 5 years of growth, the ‘JSC Kingstwo’ cultivar has remainedinsect and pathogen resistant, growing in the fields of MiddleTennessee.

7. The ‘JSC Kingstwo’ cultivar has not been observed under allconditions, and it is not known how the cultivar might respond tovarious conditions.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The first photograph (FIG. 1) shows the red-brown (172A-RHS) leaves asthey emerge from the apical leaf bud and the yellow-green andcream-green variegated leaves as one moves from the top of the seedlingto the base of the tree. All leaf petioles are red (47A-RHS). Thisseedling is the one surviving seedling that James D. Cavett rooted inJuly 2006 at 74 S&W Lane, Estill Springs, Tenn. 37330.

FIG. 2 shows the originally discovered ‘JSC Kingstwo’ as it looked in2008, two years after its discovery at 74 S&W Lane, Estill Springs,Tenn. 37330. This photograph shows the color of the leaves a couple ofweeks after the leaf emerges from its bud. Notice that the leaves arevariegated and have a large area of light green color around the majorveins. The color along the leaf margin varies from light green(145A-RHS) mixed with a light yellow (8C-RHS) or cream (41D-RHS) color.

The third photograph (FIG. 3) shows the color of mature leaves. Itexhibits a very similar variegation to the younger leaf seen in FIG. 2except that the green is much darker (137A-RHS). Notice that the petioleremains red (47A-RHS) in the more mature leaf.

The fourth photograph (FIG. 4) shows the apex of a seedling. The leafthat emerged from the apical meristem is the reddish-brown (172A-RHS)with regions of green (145A-RHS). The stunning variegation pattern ofthe leaf pigments is seen in all the leaves in this photograph. From theapex as one moves down the branch, the yellow and cream color is mixedwith large portions of green pigmentation. Notice that the greenpigmentation is darker on leaves that are further from the apex of thebranch as described in FIG. 3. The opposite arrangement of the leaves onthe branch is apparent in this photograph.

The next photograph (FIG. 5) shows early fall leaf colors. In thisphotograph, we see that the regions of the leaf that were predominatelycream or yellow in color are the first to turn a pink (56A-RHS) topurple-pink (68A-RHS) color as the fall colors develop. There is also ahint of pink to red color developing in the green-pigmented portions ofthe leaf as the chlorophyll begins to break down.

The sixth photograph (FIG. 6) shows late fall leaf colors. Late in thefall, more of the leaf develops the pink-purple color that is seen asthe leaf begins to develop fall colors (see FIG. 5). Most of the leafdevelops a deep red-brown (179A-RHS) color as the chlorophyll continuesto break down until the entire leaf is red.

In FIG. 7, one sees the flowers that emerged in March 2011 on the ‘JSCKingstwo’ seedling. Multiple flowers emerge from the flower bud in earlyspring. The flowers consist of 4 to 10 yellow-green (145B-RHS) stamensupported on a yellow stalk (23A-RHS) over the ovary.

DETAILED BOTANICAL DESCRIPTION

The following observations, measurements, and values describe treesgrown at 74 S&W Lane, Estill Springs, Tenn. 37330. The actual appearanceand characteristics of any individual tree will vary due tohorticultural practices and local conditions. The tree used in thedescription is 4 years old. Color references are made to The RoyalHorticultural Society Colour Chart except where terms of ordinarysignificance are used.

-   Botanical classification: Acer rubrum.-   Commercial classification: ‘JSC Kingstwo’ maple.-   Origin: One specific branch that had variegated loaf colors was cut    from the parental tree, an unnamed Acer rubrum. This specific branch    was the sole branch on the tree that exhibited variegation and from    this branch the six cuttings were taken and rooted.-   Parentage: The unnamed Acer rubrum tree from which the mutated limb    was obtained.-   Propagation: Asexual by softwood cuttings that were rooted in sand.-   Plant:    -   -   Growth rate.—Moderate; an average of 3 to 6 feet per year or            91 to 183 cm.        -   Form.—Oval.        -   Shape.—Oval to round.        -   Height.—Average size of the ‘JSC Kingstwo’ is 30 to 35 feet            or 914 to 1067 cm.        -   Spread.—Average size of the ‘JSC Kingstwo’ is 15 to 20 feet            or 457 to 610 cm.        -   Density.—Thick with foliage.        -   Trunk size.—2.0 to 3.0 inches or 5.0 to 7.6 cm diameter at            the base of the trunk at ground level after 5 years. The            color of the bark on the trunk of a 5-year-old tree varies            from N200C-RHS to N202C-RHS.        -   Bark.—(Trunk): Smooth, color is (N199C-RHS) textured with            tiny raised lenticels.        -   Branching arrangement.—Opposite. Angle of attachment: Ranges            from 45 to 90 degrees with 45 to 60 degrees being most            prevalent. Internodal length: Mature branches range from 3.8            to 5.0 cm or 1.5 to 2.0 inches on a 1-year-old seedling. The            average length of a typical branch is 4 to 5 feet or 122 to            152 cm, and the average diameter of a typical branch is 1.0            to 2.0 inches or 2.5 to 5.0 cm in diameter, on a 5-year-old            tree.        -   Stem.—The color of the mature stems is gray (199A-RHS). On            the new growth, the stem color is a mixture of two colors.            The youngest portion of the stem is reddish-brown (172A-RHS)            and the older portion of the stem is purple-brown in color            (166A-RHS). The average stem length is 122 to 152 cm or 4 to            5 feet; the average stem diameter is from 0.4 to 0.5 cm or            1.0 to 1.3 inches. The arrangement of leaves is opposite.            The length of new growth stem on a 5-year-old seeding ranges            30.5 to 76.2 cm or 12 to 30 inches with a diameter of 0.4 to            0.5 cm or 1.0 to 1.3 inches. The internodal length on the            5-year-old tree varies from 4.0 to 9.0 cm or 1.6 to 3.5            inches and average 6.5 cm or 3.9 inches.        -   Lenticels.—Small, but conspicuous, silver in color. They are            0.5 to 1.0 mm in length and 0.1 to 0.5 mm in width. The            color of the lenticels is 202C-RHS.        -   Leaves.—Deciduous.        -   Leaf length.—Petioles vary from 3.5 cm to 9.0 cm or 1.4 to            3.5 inches on young leaves found at the apex of the limb,            but average 6.0 cm. Leaf length of the blade varies from 5.0            cm to 8.0 cm or 2.0 to 3.1 inches in length and the width of            the leaf varies from 7.6 cm to 16.5 cm or 3.0 to 6.5 inches.            The color of the petiole is red (47A-RHS) when the leaf            first opens but the mature petiole is dark purple to red            (53A-RHS) in color and has an average diameter of 0.04            inches or 0.1 cm.        -   Average leaf width.—4.0 cm or 1.6 inches on growing branch            tips (near the apical meristem) and 8.0 cm or 3.1 inches at            the base of the branch.        -   Leaf shape.—Lobed with 3 or 5 shallow lobes.        -   Leaf margin.—Tooth.        -   Leaf texture.—Smooth on the upper and lower surfaces of the            leaf, the lower surface has some hairs and the color is            lighter on the upper side of the leaf than the lower side.        -   Leaf quantity.—Abundant.        -   Leaf color.—When the leaves first emerge from the bud, they            are red (41A-RHS) to reddish brown (172A-RHS) in color. The            red of the newly emergent leaf is quickly muted by the green            of the chlorophyll that is forming. Several weeks after            emerging from the bud, the leaf color becomes variegated and            contains a light yellow (8C-RHS) mixed with light green            (145A-RHS). The upper side of new growth (3-week-old            leaves): the 3-week-old leaves have a mixture of            reddish-brown (172A-RHS) and yellow-brown (163A-RHS); the            upper side of the most mature leaves have a mixture of dark            green (137A-RHS) and light yellow (15D-RHS) or yellow-green            (145A-RHS). Lower side of the leaf: the color mixture is            similar to the upper side at early leaf ages, but changes in            the most mature leaves to a mixture of green (194A-RHS) and            light yellow (8C-RHS) or whitish-yellow (4D-RHS).        -   Leaf ribs and veins.—The upper rib surface at the petiole            end of the leaf is dark pink-red (53C-RHS) to greenish-white            (146C-RHS) at the tip of the leaf. The lower rib surface            (leaf underside) color is dark pink-red (53C-RHS) at the            petiole end of leaf and yellow-green (145B-RHS) at the tip            of the leaf. Venation is netted.        -   Vegetative buds.—Terminal bud or apical bud is red (45A-RHS)            before the leaf emerges from the bud. Lateral buds are            conical and 0.12 to 0.4 inches or 3 to 4 mm in length and            red in color (45A-RHS).        -   Leaf apex.—The leaf apex is acute.        -   Base descriptor.—Rounded.-   Flowers: Seedless but produces flowers. Flowers appeared in early    March 2011. There were 3 to 4 flower buds at each node (FIG. 7).    There were 4 to 10 stamen (FIG. 7) in each flower and were    yellow-green (145B-RHS). The stalk of the stamen is yellow    (23A-RHS). The inflorescence typically is 15 to 20 mm from the base    of the peduncle to the tip of the anther, and 3 to 5 mm in diameter    from petal to petal. Due to the sterile nature of this specimen, the    flowers do not have pistils, and therefore no ovaries or stigma, and    the flowers do not pollenate.-   Petals: 6-8 petals on each flower, the petals are 3 to 5 mm in    length and 1 to 2 mm in diameter. Ovular in shape with a smooth    texture both inside and out. The apex on the petals in acute with a    tooth margin. The outside color of the petals is orange-red    (39B-RHS), and the inside color of the petals is a light pink    (65B-RHS).-   Sepals: The sepals are 3 to 5 mm in both length and diameter. There    are hexagonal in shape with a smooth texture on both inside and out.    The apex of the sepals is acute with a tooth margin. The color both    inside and out is dark pink red (53C-RHS).-   Flower buds: The buds of the flowers are circular in shape. They are    4 to 6 mm in diameter and 3 to 8 mm in length.-   Peduncles: The peduncles are 1 to 4 mm in length and 0.2 to 0.5 mm    in diameter. The peduncles are an orange red (31D-RHS).-   Anther: The anther length is 0.5 mm to 1 mm in length, and are    yellow-green (145A-RHS) as the flower emerges from the bud, and    eventually turns a dark green (137A-RHS) as the flower matures.-   Disease and pest resistance: No known susceptibility to diseases or    pests common to Acer rubrum.

What is claimed:
 1. A new and distinct cultivar of Acer rubrum treenamed ‘JSC Kingstwo’ as illustrated and described herein.